The present invention relates to a method for improving the accuracy of connection made between a lead wire and a slip-on type electrical terminal to which the lead wire is permanently attached.
A terminal of a type to which the invention can be applied is illustrated in FIG. 1 of the attached drawings. The terminal has a slip-on contact portion a and an electrical wire securing portion including conductor-crimping tabs b and insulation-crimping tabs c. In accordance with the conventional method, to attach a lead wire to the terminal, the insulation d is stripped from the wire by a predetermined length to bare the conductor e. The end of the wire so prepared is placed between the tabs b and c and the tabs b and c bent over to fix the wire to the terminal.
However, if the length of the exposed conductor e is too long or too short, the positional relationship between the terminal and the wire may not be proper. If, for example, the length of the exposed conductor e is too long or the end of the wire is positioned too far forwardly in the terminal, as shown in FIG. 2, the end of the conductor has a tendency to fray, potentially causing the terminal when installed to be short-circuited to another member. Also, inaccuracies in stripping the insulation d and aligning the end of the wire with the terminal can result in a portion of the insulation d being clamped by the conductor-crimping tabs b, as illustrated in FIG. 3, resulting in a poor connection between the wire and the terminal.
A further difficulty to which the invention is addressed relates to the manner in which the terminals are severed from the chain in which they are supplied and transported to the machine which attaches the wires to the terminals. That is, these terminals are ordinarily supplied in the form of a long chain, with the terminals either arranged serially, as shown in FIG. 4 where the terminals A are connected end to end via coupling segments B, or in parallel form, as shown in FIG. 5 where the terminals A are coupled on both sides via linear coupling segments C and C'. Just before the terminals are moved to the position where the leads wires are attached, the coupling segments B or C and C' are severed.
If, however, the remaining portion of a coupler segment on either end of the terminal after the severing operation is too long, the remaining portion may in use come into contact with another member, thereby short-circuiting the terminal. Also, the insulation of the lead wire can be damaged if the remaining portion of the coupler segment at the rear (lead wire end) of the terminal is too long. On the other hand, if, for instance, the coupler segment at the front end of the terminal is cut off too short, damage to the contact portion of the terminal may occur.